In the assembly of fences and railings consisting of picket elements, a labor-intensive aspect associated with the construction of such fences has resided in the attachment of the picket elements thereof with the transverse members of the fence. More particularly, in recent years, certain metallic picket fences consisting of hollow tubular elements have come into vogue to the extent that, in many applications, wooden picket fences are now rarely used. Metal picket fences of this type are shown in FIGS. 1, 2 and 11 of the Drawings.
A difficult and laborious aspect of the assembly of such metal picket fences lies in the connection (also known as the swedge) of the tubular pickets at the points thereof at which they pass through or within the horizontal cross-members of the fencing system. Historically, this connection has been effected by means of welding of the vertical pickets at each point that one passes through a transverse horizontal member. This process is time-consuming, inexact and often unaesthetic in that the paint or other coating upon the elements of the fence may be broken, burnt otherwise rendered unsightly by such welding thereupon. Proper fusion of the paint finish at welded points is therefore nearly impossible. Thusly, cracking, pealing, chipping is a result.
Where, in the past, screws were used to secure the respective members, the result was that of rusting, vibrating and loosening of the screws and eventually of their falling-off of the structure.
The instant invention is concerned with an assembly method, the usage of which will obviate the need for welding or any other external process to effect the connection of hollow or tubular vertical picket elements within transverse hollow or tubular members of a metal fence system.
In addition to the need for a method of more easily assembling metal picket fences of the type shown in the drawings, there exists a need for a constructional method for the positioning of emblems, and the like, upon the tops of picket fences. Such a fence is shown in the view of FIG. 11.
In addition to the need for an improvement in existing methods of assembly of tubular picket fences, there exists numerous other mechanical systems in which one or more elongated tubular constructional element must be secured to a second tubular constructional element. One example of a structure of this type appears in FIG. 14 in which there is shown a metal ladder. Metal ladders are typically formed of a series of hollow transversely disposed step elements which are secured to the internal structure of a pair of elongated vertical side elements. In the construction of such a ladder, it is necessary to either secure the transverse elements to the longitudinal elements or to secure the longitudinal elements to the transverse elements. The latter is more cost-effective and is facilitated by the present method.
In general, the instant method affords a technique for the reaching of securement sites that are separated from the worker at a site otherwise difficult to reach, or in which the work site is enclosed by the geometry of the constructional element and thereby rendered difficult to access. This is typically the case where a work location is enclosed within an elongated tubular structure which, typically, will have an uniform cross-section.
It is in response to the long-felt need for such a constructional method that the present invention is directed.